Holland will join teammates Alex Gordon and Salvador Perez in New York; all three players are appearing in the game for the first time. Kansas City has not sent three players to the All-Star Game since 1988, when George Brett, Kurt Stillwell and Mark Gubicza were all selected to the squad.
The right-hander has served as the Royals closer since the team traded Jonathan Broxton to the Cincinnati Reds at the trade deadline last season. Holland dominated opposing hitters in the first half of 2013, posting a 1.80 ERA with 22 saves over 35 innings. The closer has struck out 44 percent of the batters he has faced this season, which leads MLB, and has struck out the side six separate times.
Iwakuma pitched for the Mariners on Sunday, making him unavailable to throw again Tuesday. The rookie pitcher entered Sunday with a 7-4 record and 2.97 ERA in 19 starts.